This disclosure relates to a processing method compatible with standard and flexible nonvolatile memory devices for use in portable electronic devices, sensors, displays, or the like.
Two-terminal circuit elements may be used as memory devices, or for logic functionality, for example. A two-terminal circuit may include an electrically variable material between two electrodes. Such a circuit element, with a non-linear and time-dependent relationship between the change in current and the change in voltage, may also be known as a memristor.
One type of memristor includes a region of doped titanium dioxide arranged adjacent a region of undoped titanium dioxide. Applying a voltage to the memristor is thought to cause migration of the dopants between the doped and undoped regions that contributes to changing the electric resistance of the memristor.
One problem associated with titanium dioxide memristors is that the processing techniques may be expensive and require relatively tight control of processing parameters. For instance, titanium dioxide memristors may be fabricated using in-vacuo oxidation of titanium, ozone techniques, or sputtering. Typically, such techniques require expensive equipment and may not be suitable for making flexible memory devices. Additionally, the processing parameters, such as times, temperatures, and oxygen levels, must be tightly controlled to achieve the desired doped and undoped regions.